Butter them up

When it comes to the humble spud, beauty is definitely more than skin deep. Mashed, crushed or puréed, they are fabulous. But before you reach for the peeler, take a little time to understand their needs

Whether it is the ethereal, silky pommes purée of haute cuisine, the good old-fashioned British mash or the à la mode crushed potatoes, there is a technique for preparing the humble spud that not only gives astonishing results but also is surprisingly convenient.

At the restaurant, we used to make potato purée twice a day, keeping it warm in a water bath, before whisking in hot milk as and when necessary. This whole process was not only a complete pain, but it also meant that the leftover purée had to be discarded - an immoral and costly waste of food, in my opinion.

In his book, The Man Who Ate Everything, Jeffrey Steingarten devotes an entire chapter to puréed potatoes, in which he explains that manufacturers of dried potato flakes had to find a way to minimise the amount of gluey starch present before the potatoes were dried. Otherwise, the starch would become concentrated during the drying process, producing a substance not dissimilar to wallpaper paste. The process that they adopted to prevent this disaster involved pre-soaking the potatoes at room temperature, so that the starch contained in the potatoes begins to gelatinise. The starch molecules then remain separate from each other during the final cooking process, which involves putting them into salted, simmering water until cooked. As a result, the starch, now dispersed in the potato, will not clump together before freeing itself to make the dreaded gluey purée.

The real beauty of adapting this approach for the home or professional kitchen is that you can make the base in advance. When you want to serve it, simply reheat the potatoes, whisking in hot milk until the desired consistency has been reached.

You will notice the difference between the purée produced by this method and that from the more traditional approach. The resulting dish has a really crumbly texture to it, with no gluey character whatsoever.

But be warned: there is one disadvantage to puréeing potatoes in this way, and that is that the margin for error really is not great. To ensure perfect results, either arm yourself with a trusty digital probe or a thermometer that is calibrated to fahrenheit.

Basic recipe

This procedure forms the template from which you can produce potatoes that are guaranteed to please.

1.5kg potatoes (Belle de Fontenay or Charlotte varieties are ideal)

Peel the potatoes and cut them into slices of about 2.5cm thick. The important thing here is that the slices need to be of uniform thickness, as what may appear to the eye to be only a small difference in thickness might well be as much as 15%. This would mean that a 30-minute cooking time for one piece may well be five minutes too short for another. After slicing, leave the slices in a colander under cold running water for a few minutes, to wash off any excess starch, then drain.

Now for the soaking process: fill a casserole large enough comfortably to hold the potatoes and water. The quantity of water should be enough to cover the potatoes by a couple of centimetres. Do not put the potatoes in yet.

Very gently heat the pan to 175F and wait for 10 minutes to make sure that the temperature remains constant. Now add the potatoes. The temperature should drop to 165F. Maintain this temperature for 30 minutes. Drain the potatoes, and immediately place in a bowl under running water until quite cold. Now the potatoes are ready to be cooked.

Bring another pan of water to the simmer, and salt it so that it has the taste of seawater. Add the potatoes and cook until soft. The potatoes are ready when a knife easily penetrates them, with no resistance. Be careful not to overcook them, else the purée will become too wet.

Drain the potatoes and run them under cold water until they have completely cooled down. Dry them thoroughly by putting the potatoes back in a pan on a low heat and gently shaking them. Now they are ready to be mashed, crushed or puréed.

Good old-fashioned mash

Simply add butter or olive oil, or a combination of the two, together with some simmering milk or cream, or, again, a mixture of the two. Then mash the potatoes as you would do normally. If you do not want to serve immediately, add only the butter and allow the mix to cool down before putting it in an airtight container and keeping it in the fridge. When you want to serve, heat gently in a pan, whisking in a little more hot milk and cream to taste.

Crushed potatoes

The aim of this dish is to end up with mashed potato that still has small chunks in it, to give you a variation in texture. With the back of a fork, crush the potatoes while adding butter and or olive oil, along with other ingredients of your choice. For example, you can add chopped shallots, confit tomatoes, chopped herbs such as parsley, chives, basil or coriander, olives, capers or cooked bacon.

Once again, if not serving immediately, cool and refrigerate the potato before adding the flavourings. With this dish, you can simply re-heat the potatoes in the oven before adding the extra flavours.

Pommes purée

At the restaurant, we make this dish with just milk and butter - quite large quantities of butter, in fact: around 400g of unsalted butter for every kilogram of potatoes. Personally, if I was making this for the children, I'd use less butter; say, 200g per kg of potato. If, however, the purée is for a big lunch or special dinner, I'd increase the quantity to 300g. Ideally, you should use a ricer for this job, although a vegetable mill should do the trick, too.

Cut the butter into cubes of about one inch and place them in a large bowl. With the cooked potatoes still hot, push the vegetables through the ricer and on to the cubed butter. The ricer works best because you are not working the potatoes across a sieve, which will produce a more gluey mash. For the same reason, never use a food processor, unless you want your guests to be eating the savoury equivalent of bubblegum.

At the restaurant, we then pass the purée through a flat, very fine-meshed drum sieve, which gives it a lighter, more silky texture. It's up to you if you want to do the same, though I'd recommend trying it at least once. You can prepare the purée in advance up to this stage. It will keep in the fridge for a few days.

To serve, re-heat gently in a pan while gradually whisking in a little simmering milk. To the purée you could add melted cheese, chopped herbs or grain mustard. The choice is yours.